Re: [RFC][PATCH 0/2] staging: alarm-dev: compat_ioctl support

From: John Stultz
Date: Fri Jan 11 2013 - 17:07:05 EST


On 01/11/2013 02:03 PM, Colin Cross wrote:
On Fri, Jan 11, 2013 at 1:48 PM, John Stultz <john.stultz@xxxxxxxxxx> wrote:
This is a first-pass at implementing compat_ioctl support for
Android's alarm-dev driver in staging.

The first patch is some refactoring to cleanup and separate the
copying of user data from the logic, and the second patch adds
the compat_ioctl support.

As noted in the patch, the only really squirly bit is the handling
of ANDROID_ALARM_SET_OLD and ANDROID_ALARM_SET_AND_WAIT_OLD. These
are present to support existing older Android applications.
Unfortunately these cause ioctl number aliasing issues with
the compat ioctls, so on 64bit they are only supported in the
compat patch (since any existing android app old enough to use
them are likely 32bit).

I'd appreciate feedback from the Android devs on if this is
an ok assumption and if it might be reasonable to establish
some sort of a phase-out timeline for the _OLD ioctl support.
The "support old userspace code" comment for those two ioctls has been
there since pre-Android 1.0. Those apis are not exposed to Android
apps, I don't see any problem deleting them.

That's great! I'll rework the patch set to include dropping them.

Thanks for the extra insight here!
-john
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/